The EU-funded iCIRRUS project was successfully completed with a final presentation at Telekom Slovenia in Ljubljana. The aim of the three-year project was to develop various solutions for the intelligent cloud-Radio Access Network (RAN) in the new 5G mobile communications standard. This new approach puts handovers into effect faster and makes the system more robust against interference; it also enhances the security of communication by preventing unauthorized interception and external attacks. The Fraunhofer HHI was involved in the project with its Photonic Networks and Systems Department.

Wireless capabilities are increasingly virtualized by means of Cloud RANs and can be positioned flexibly in the network depending on the application. iCIRRUS has developed innovative fronthaul solutions with data rates up to 100 Gb/s as well as an associated cloud solution to achieve the goals of a 1000-fold area capacity at a 10 to 100-fold higher user data rate (in comparison to 4G LTE) via Ethernet that is commonly used in the transmission network.

„In the iCIRRUS project, we were able to demonstrate for the first time an Ethernet-based fronthaul solution for mm-wave signals that achieves the high data rates expected for 5G,“ comments Kai Habel, project manager at Fraunhofer HHI, on the successful completion of the project.

Fraunhofer HHI’s contribution to the project was the development of a synchronous fronthaul solution for 5G. It provides mm-wave radio signals at a rate of 60 GHz at the nearest base station from where the mobile device can be reached. Unlike with 4G LTE, however, the signals of 5G are generated and detected in the cloud, thus rendering it necessary to have the option of transmitting them over several nodes in the transmission network using optical fiber. Very high synchronization requirements must be met for interference suppression in mobile communications. The real-time capable transmission system of Fraunhofer HHI is able to transmit data with up to 2.5 Gb/s error-free in the flexible 5G Cloud-RAN scenario for the first time.

The project was realized with the partners Orange Networks, Telekom Slovenia, Primetel and Wellness Telecom, the telecommunications equipment suppliers ADVA and VIAVI, IAF GmbH, the universities of Kent (as coordinator) and Essex and Fraunhofer HHI and had a total budget of approx. 3.8 million euros. The project went public with the offered Ethernet-based cloud-RAN technology via a wide range of scientific publications and various system demonstrations at international events such as the Mobile Word Congress, ECOC and EUCNC.